SUV39H1通过表观遗传调控促进宫颈癌中CCL22-CCR4表达OACSTPCD

Objective To investigate the mechanism of epigenetic regulation of C-C-motif ligand 22(CCL22)and CC-chemokine receptor 4(CCR4)in cervical cancer and their roles in cervical carcinogenesis.Methods CCL22 and CCR4 mRNA levels and DNA methylation levels of their gene promoters were detected in 16 cases of cervical cancer and 16 cases of normal cervical tissues by RT-qPCR and MS-PCR,respectively.SiHa and HeLa cells were treated with different concentrations of 5-Aza,a DNA methyltransferase inhibitor(0,2.5,5 μmol/L),and then RT-qPCR was used to detect the expression levels of CCL22 and CCR4 mRNA in these cells.Cervical cancer SiHa and HeLa cells were transfected with a lentiviral expression vector overexpressing the histone methyltransferase(SUV39H1)and a control plasmid,named as SUV39H1-OE group and SUV39H1-NC group.SiHa and HeLa cells were transfected with SUV39H1-specific siRNA and control siRNA,respectively,named as siSUV39H1 group and siNC group.Then RT-qPCR was used to detect the changes of CCL22 and CCR4 mRNA expression in SiHa and HeLa cells,and MS-PCR was used to detect the methy-lation levels of CCL22 and CCR4 gene promoters in these cells.Chromatin immunoprecipitation was used to detect the enrichment of H3K9me3 mediated by SUV39H1 at CCL22 and CCR4 gene promoters.Results The expresions of CCL22 and CCR4 mRNA were significantly higher in cervical cancer tissues than those in normal cervical tissues(P<0.05),and the methylation levels at their gene promoters were lower(P<0.05).The promoters of CCL22 and CCR4 genes showed partial methylation in SiHa and HeLa cells.After de-methylation treatment,the expression levels of CCL22 and CCR4 mRNA were increased in a concentration-dependent manner(P<0.05).Compared with SUV39H1-NC group,CCL22 and CCR4 mRNA expressions in cervical cancer cells were increased in SUV39H1-OE group and the promoter methylation was decreased(P<0.05).Compared with siNC group,CCL22 and CCR4 mRNA expressions were decreased in siSUV39H1 group,and the promoter methylation was increased(P<0.05).Chromatin immunoprecipitation showed H3K9me3 enrichment in the CCL22-CCR4 gene promoter regions in SiHa and HeLa cells(P<0.05).Conclusion SUV39H1-H3K9me3 is involved in the epigenetic regulation of the chemokine CCL22 and its receptor CCR4 in cervical cancer cells.